93 grand cherokee starting issues
#16
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
Do you think a coil would do that tho?intermittently work? Sorry I don't know much about engines mainly just drivetrains ha
#17
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Year: 1993
Model: Grand Cherokee
Engine: 5.2
do you know if this is the stock coil? If you're not sure, chances are it very well might be! That coil is pretty cheep. Practically dirt cheep if you look hard enough! Even an MSD only costs like $50 brand new off the internet.
#18
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Year: 1993
Model: Grand Cherokee
Engine: 5.2
It could! As things get hot and cold they expand and contract. If its an old coil it will do just that! As it heats up, the metal inside expands thus shortening the gap between its spool or magnetic plates. Which will make the problem go away or ease when it gets hot, and only happen when its cold.
All this expanding and contracting over the years will create a bigger gap within parts of itself that get smaller when hot but even bigger after it cools down. Consider this normal wear and tare for something thats almost 20 years old. I say, for an 18 year old ignition system, its seen better days. and for $50... its worth replacing!
#19
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
Okay so i put a new TPS on it because it was laying around. When I have the intake off and its first tryin to start but it can't the IAC will make a screaming noise, but when it gets running it doesn't. This noise hasn't always been there could that have somethin to do with it? I replaced the coil and still nothing
#20
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
So I pulled out the CPS today, went to get a new one but he parts store don't have one until tomorrow so ill keep you updated- hope this fixes it!
#23
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
Changed crank position sensor. Didn't fix anything, I'm at a loss I wish I knew someone who has had this problem before. Guess I might be missing moab this month
#24
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
So now it will die while I'm driving but only when I'm coming to a stop, it starts right back up afterwards
#26
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
Ya I replaced the coil, fuel pump is nearly new and I can hear it priming and it has fuel pressure when starting and idling. Tell me about it this is my daily driver I have been scrounging rides from my friends. My next thought is the PCM
#27
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
I just pulled the PCM, I took the screws out and opened it up. All I can see is what appears to be plastic molding? Its all cracked is this bad?
#28
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
It is running way way lean, unplugged the o2 sensor and it ran better. Would an o2 sensor do that, it also didn't throw a code when it was unplugged
#29
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Year: 1993
Model: Grand Cherokee
Engine: 5.2 V8, Dual cold air, dual batts, E-fan, Sanden OBA
Plugged my PCM into my buddies zj, it idled really low but didn't seem to have a hard time starting. Plugged it back into mine and same no start
#30
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Year: 1987
Engine: Check
Prolly idled low because it needed to re-learn that other truck's fuel parameters.
Nothing inside the PCM should be cracked, but that doesn't mean its broken. Electrical components could still be OK, usually you look for burnt/charred looking pieces.
Your o2 sensor should trip a CEL if unplugged. It may just need a little while to actually show the CEL, though.
I'm not convinced though that the o2 sensor is the problem. It may just be a small hint at what the real issue is.
Nothing inside the PCM should be cracked, but that doesn't mean its broken. Electrical components could still be OK, usually you look for burnt/charred looking pieces.
Your o2 sensor should trip a CEL if unplugged. It may just need a little while to actually show the CEL, though.
I'm not convinced though that the o2 sensor is the problem. It may just be a small hint at what the real issue is.